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1.
Health Promot Pract ; : 15248399231192989, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37649378

RESUMO

OBJECTIVE: The COVID-19 pandemic highlighted the role that local health departments (LHDs) have in cross sector can address alone, including the work of value alignment and the strategic use of organizational authorities. The practices by which LHDs used their authorities to conduct cross-sector work during the pandemic need exploration. METHOD: We conducted semi-structured interviews with 19 public health leaders from metropolitan LHDs across the United States. Our interview guide assessed the values that LHD leadership prioritized in their cross-sector work as well as the range of organizational authorities they leveraged to influence external decision-making in other sectors. RESULTS: We found that LHDs approached cross-sector work by leaning on diverse values and authorities, each with unique implications for their work. The LHDs emphasized their approach to value alignment on a sector-by-sector basis, strategically using diverse organizational authorities-economic, political, moral, scientific, and logistical. While each authority and value we assessed was present across all interviewees, how each shaped action varied. Internally, LHDs emphasized certain authorities more than others to the degree that they more closely aligned with prioritized core values. CONCLUSION: Our findings highlight the ongoing need for LHD leadership to improve their ability to effectively communicate public health values and the unique authorities by which health-supporting work can be facilitated, including how this message must be adapted, depending on the specific sectors with which the LHD needs to partner and the governance arrangement in which the LHD is situated.

2.
Int J Mol Sci ; 23(10)2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35628597

RESUMO

Pleural mesothelioma (PM) is an aggressive tumor with few therapeutic options. Although patients with epithelioid PM (ePM) survive longer than non-epithelioid PM (non-ePM), heterogeneity of tumor response in ePM is observed. The role of the tumor immune microenvironment (TIME) in the development and progression of PM is currently considered a promising biomarker. A few studies have used high-throughput technologies correlated with TIME evaluation and morphologic and clinical data. This study aimed to identify different morphological, immunohistochemical, and transcriptional profiles that could potentially predict the outcome. A retrospective multicenter cohort of 129 chemonaive PM patients was recruited. Tissue slides were reviewed by dedicated pathologists for histotype classification and immunophenotype of tumor-infiltrating lymphocytes (TILs) and lymphoid aggregates or tertiary lymphoid structures (TLS). ePM (n = 99) survivors were further classified into long (>36 months) or short (<12 months) survivors. RNAseq was performed on a subset of 69 samples. Distinct transcriptional profiling in long and short ePM survivors was found. An inflammatory background with a higher number of B lymphocytes and a prevalence of TLS formations were detected in long compared to short ePM survivors. These results suggest that B cell infiltration could be important in modulating disease aggressiveness, opening a pathway for novel immunotherapeutic approaches.


Assuntos
Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Estruturas Linfoides Terciárias , Humanos , Mesotelioma/genética , Neoplasias Pleurais/genética , Sobreviventes , Estruturas Linfoides Terciárias/patologia , Microambiente Tumoral/genética
3.
Haematologica ; 104(3): 533-545, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30262563

RESUMO

B-cell precursor-acute lymphoblastic leukemia modulates the bone marrow (BM) niche to become leukemia-supporting and chemo-protective by reprogramming the stromal microenvironment. New therapies targeting the interplay between leukemia and stroma can help improve disease outcome. We identified ActivinA, a TGF-ß family member with a well-described role in promoting several solid malignancies, as a factor favoring leukemia that could represent a new potential target for therapy. ActivinA resulted over-expressed in the leukemic BM and its production was strongly induced in mesenchymal stromal cells after culture with leukemic cells. Moreover, MSCs isolated from BM of leukemic patients showed an intrinsic ability to secrete higher amounts of ActivinA compared to their normal counterparts. The pro-inflammatory leukemic BM microenvironment synergized with leukemic cells to induce stromal-derived ActivinA. Gene expression analysis of ActivinA-treated leukemic cells showed that this protein was able to significantly influence motility-associated pathways. Interestingly, ActivinA promoted random motility and CXCL12-driven migration of leukemic cells, even at suboptimal chemokine concentrations, characterizing the leukemic niche. Conversely, ActivinA severely impaired CXCL12-induced migration of healthy CD34+ cells. This opposite effect can be explained by the ability of ActivinA to increase intracellular calcium only in leukemic cells, boosting cytoskeleton dynamics through a higher rate of actin polymerization. Moreover, by stimulating the invasiveness of the leukemic cells, ActivinA was found to be a leukemia-promoting factor. Importantly, the ability of ActivinA to enhance BM engraftment and the metastatic potential of leukemic cells was confirmed in a xenograft mouse model of the disease. Overall, ActivinA was seen to be a key factor in conferring a migratory advantage to leukemic cells over healthy hematopoiesis within the leukemic niche.


Assuntos
Ativinas/genética , Biomarcadores Tumorais , Leucemia-Linfoma Linfoblástico de Células Precursoras B/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Ativinas/metabolismo , Animais , Medula Óssea/patologia , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação Leucêmica da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Células Estromais/metabolismo
4.
Nanotechnology ; 29(22): 225604, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29517488

RESUMO

Ibuprofen (IBU) is a widespread drug used to treat both acute and chronic disorders. It is generally taken orally but the free drug can induce the irritation of the gastric mucosa due to its acid nature. In literature, different approaches have been adopted to prevent the release in the stomach, such as physical entrapment with film-coated tablets and drug-conjugates. Nevertheless, these solutions have many disadvantages, including the fast release of the drug and the difficulty to swallow the tablet, especially for children who may vomit or refuse the tablet. For this reason, in this work, novel formulations are proposed that do not require the encapsulation of the drug into a solid form and, in turn, their assumption as a pill. IBU has been linked to different types of methacrylates via ester bond in order to produce pH-responsive macromolecular monomers. The novelty is related to the use of these drug-conjugates macromonomer for the production of nanoparticles (NPs) via emulsion polymerization (EP), using water as solvent. The final emulsion is able to load up to 30 mg ml-1 of IBU, so less than 10 ml is required to be assumed to reach the minimum therapeutic dose of the drug (200 mg). Finally, the release of IBU from these novel drinkable formulations has been investigated in the gastric and intestinal simulated fluids to show the preferential release of IBU from the NPs in basic conditions. A comparison with an existing oral suspension has been performed to highlight the slower release in acid environment of these new formulations. Afterwards, the IBU loaded NPs were tested in vitro showing lower toxicity compared to the free drug.


Assuntos
Sistemas de Liberação de Medicamentos , Ibuprofeno/administração & dosagem , Ibuprofeno/farmacologia , Nanopartículas/química , Administração Oral , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Ibuprofeno/química , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Polímeros/síntese química , Polímeros/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta
5.
Am J Public Health ; 107(S3): S223-S228, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29236539

RESUMO

Health professionals, including social workers, community health workers, public health workers, and licensed health care providers, share common interests and responsibilities in promoting health equity and improving social determinants of health-the conditions in which people live, work, play, and learn. We summarize the underlying causes of health inequity and comparatively poor health outcomes in the United States. We describe barriers to realizing the hope embedded in the 2010 Patient Protection and Affordable Care Act, that moving away from fee-for-service payments will naturally drive care upstream as providers respond to greater financial risk by undertaking greater prevention efforts for the health of their patients. We assert that health equity should serve as the guiding framework for achieving the Triple Aim of health care reform and outline practical opportunities for improving care and promoting stronger efforts to address social determinants of health. These proposals include developing a dashboard of measures to assist providers committed to health equity and community-based prevention and to promote institutional accountability for addressing socioeconomic factors that influence health.


Assuntos
Política Ambiental , Reforma dos Serviços de Saúde/organização & administração , Equidade em Saúde/organização & administração , Qualidade da Assistência à Saúde , Agentes Comunitários de Saúde , Feminino , Política de Saúde , Humanos , Masculino , Patient Protection and Affordable Care Act
6.
Mol Pharm ; 13(1): 40-6, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26623665

RESUMO

Polymer nanoparticles (NPs) represent a promising way to deliver poorly water-soluble anticancer drugs without the use of unwanted excipients, whose presence can be the cause of severe side effects. In this work, a Cremophor-free formulation for paclitaxel (PTX) has been developed by employing PEGylated polymer nanoparticles (NPs) as drug delivery carriers based on modified poly(ε-caprolactone) macromonomers and synthesized through free radical emulsion polymerization. Paclitaxel was loaded in the NPs in a postsynthesis process which allowed to obtain a drug concentration suitable for in vivo use. In vivo experiments on drug biodistribution and therapeutic efficacy show comparable behavior between the NPs and the Cremophor formulation, also showing good tolerability of the new formulation proposed.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Paclitaxel/química , Polietilenoglicóis/química , Polímeros/química , Polimerização
7.
Biomacromolecules ; 17(3): 744-55, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26791775

RESUMO

An integrated platform to assess the interaction between nanocarriers and biological matrices has been developed by our group using poly methyl-methacrylate nanoparticles. In this study, we exploited this platform to evaluate the behavior of two biodegradable formulations, poly-ε-caprolactone (PCL3) and poly lactic-acid (PLA8), respectively, in cellular and animal models of triple-negative breast cancer (TNBC). Both NPs shared the main physicochemical parameters (size, shape, ζ-potential) and exclusively differentiated on the material on which they are composed. Our results showed that (1) PLA8 NPs, systemically injected in mice, underwent rapid degradation without penetration into tumors; (2) PLA8 NPs were not internalized in the human TNBC cell line (MDA-MB-231); (3) PCL3 NPs had a longer bioavailability, reached the tumor parenchyma, and efficiently penetrated in MDA-MB-231 cells. Our data highlight the relevance of the material selection to both improve bioavailability and target tropism, and make PCL3 NPs an interesting tool for the development of nanodrugs against TNBC.


Assuntos
Portadores de Fármacos/farmacocinética , Nanocápsulas/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/efeitos adversos , Portadores de Fármacos/química , Feminino , Humanos , Camundongos , Nanocápsulas/efeitos adversos , Poliésteres/química , Distribuição Tecidual
8.
Nanotechnology ; 27(12): 125102, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26891480

RESUMO

Small interfering RNA (siRNA) is receiving increasing attention with regard to the treatment of many genetic diseases, both acquired and hereditary, such as cancer and diabetes. Being a high molecular weight (MW) polyanion, siRNA is not able to cross a cell membrane, and in addition it is unstable in physiological conditions. Accordingly, a biocompatible nanocarrier able to deliver siRNA into cells is needed. In this work, we synthesized biocompatible positively charged nanoparticles (NPs) following a two-step process that involves ring opening polymerization (ROP) and emulsion free radical polymerization (EFRP). Firstly, we proved the possibility of fine tuning the NPs' characteristics (e.g. size and surface charge) by changing the synthetic process parameters. Then the capability in loading and delivering undamaged siRNA into a cancer cell cytoplasm has been shown. This latter process occurs through the biodegradation of the polymer constituting the NPs, whose kinetics can be tuned by adjusting the polymer's MW. Finally, the ability of NPs to carry siRNA inside the cells in order to inhibit their target gene has been demonstrated using green flourescent protein positive cells.


Assuntos
Nanopartículas/química , Polímeros/síntese química , RNA Interferente Pequeno/farmacocinética , Animais , Citoplasma/genética , Humanos , Camundongos , Neoplasias/genética , Neoplasias/terapia , Tamanho da Partícula , Polímeros/química , RNA Interferente Pequeno/química , Terapêutica com RNAi
9.
J Public Health Manag Pract ; 22 Suppl 1: S100-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26599022

RESUMO

Behavioral health disparities are not usually considered part of the same system of health disparities. However, the California Department of Public Health focused its health equity strategies on reducing behavioral health disparities through its California Statewide Plan to Promote Health and Mental Health Equity. This statewide plan was developed through a community-wide stakeholder engagement and outreach process. In addition, the California Reducing Disparities Project is a prevention and early intervention effort to reduce mental health disparities in underserved populations. This strategic plan represents the voice of several racial/ethnic communities, such as African American, Asian and Pacific Islander, Latino, Native American, as well as lesbian, gay, bisexual, transgender, and queer and questioning communities in California, through 5 strategic planning workgroups. The workgroups were composed of a broad range of stakeholders, including community leaders, mental health care providers, consumer and family members, individuals with lived experience, and academia. This case example highlights the various efforts of California's Office of Health Equity in eliminating behavioral health disparities and promoting mental health equity, as well as discusses the unique statutory and regulatory role of the Office of Health Equity's deputy director.


Assuntos
Equidade em Saúde/normas , Serviços de Saúde Mental/normas , Negro ou Afro-Americano/estatística & dados numéricos , California , Promoção da Saúde/normas , Acessibilidade aos Serviços de Saúde/normas , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Hispânico ou Latino/estatística & dados numéricos , Humanos , Serviços de Saúde Mental/provisão & distribuição , Grupos Minoritários/estatística & dados numéricos , Minorias Sexuais e de Gênero/estatística & dados numéricos
10.
J Public Health Manag Pract ; 22 Suppl 1: S87-93, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26599035

RESUMO

CONTEXT: For many years, the Minnesota Department of Health (MDH) has been intentionally engaged in decreasing race- and ethnicity-based health disparities in the state. It has seen modest success in some areas, but overall, the disparities remain. Research over the last several decades has shown that race- and ethnicity-based health disparities are the result of persistent social and economic inequities, which have a greater influence on health outcomes than either individual choices or interventions by the health care system. SETTING: The MDH leaders recognized that to focus health improvement efforts solely on access to health care and individual behavior change (the traditional public health approaches of the last 30 years) would fail to make adequate advances in eliminating health disparities. Working with a statewide group known as the Healthy Minnesota Partnership, MDH decided to shift the public conversations about health in Minnesota to focus on the factors that actually create health. CONCLUSIONS: This effort to develop and implement a new narrative about health, focused on upstream issues such as education, employment, and home ownership, led to an emphasis on health in all policies approach for MDH and its partners. This case example will highlight Minnesota's efforts and discuss the new Council on Institutional Collaboration initiative in partnering large research universities with state health departments in addressing the social determinants of health.


Assuntos
Equidade em Saúde/normas , Política de Saúde/tendências , Saúde Pública/tendências , Racismo/prevenção & controle , Comportamento Cooperativo , Equidade em Saúde/tendências , Humanos , Minnesota , Saúde Pública/métodos , Racismo/tendências
11.
J Public Health Manag Pract ; 22 Suppl 1: S94-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26599036

RESUMO

CONTEXT: Oklahoma has a history of strong partnerships with their tribal health leaders and tribal communities. In 2012, the Oklahoma State Department of Health (OSDH) established the Office of the Tribal Liaison, as Oklahoma has 39 tribal nations in the state, of which 38 are federally recognized. The Office of the Tribal Liaison is responsible for promoting relationships with Oklahoma Tribal Nations and implementing the OSDH Tribal Consultation policy. SETTING: The strength of the partnership between the OSDH and the Tribal Nations enabled a new collaboration during an event hosted by a tribal casino event center that brought tattoo artists to provide tattoos to patrons over 3 days. Licensure issues that crossed the jurisdiction boundaries of the OSDH emerged before the event, which required the OSDH, Indian Health Service, and the Tribal Nation to work together to protect the public's health. The 3 jurisdictions drew upon their previously established partnership, OSDH's tribal consultation policy, and their open and trusting relationship to come together quickly to protect the public's health. CONCLUSIONS: This event and interjurisdictional partnership highlighted the importance of adopting the "Spectrum of Processes for Collaboration and Consensus-Building" model as outlined by Orenstein et al to help guide and support state, tribal, and federal collaborations. This case example highlights the opportunities for collaboration between different regulatory public health and tribal bodies to improve the communities' health.


Assuntos
Comportamento Cooperativo , Administração em Saúde Pública/métodos , United States Indian Health Service/organização & administração , Humanos , Oklahoma , Administração em Saúde Pública/tendências , Estados Unidos , United States Indian Health Service/normas , United States Indian Health Service/tendências
13.
Tumour Biol ; 35(10): 9967-75, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25008568

RESUMO

Colorectal cancer is the third most common cancer in the world, with 1.2 million new cancer cases annually. Chalcones are secondary metabolite precursors of flavonoids that exhibit diverse biological activities, including antioxidant and antitumor activities. The aim of this study was to investigate the antiproliferative effect of new synthetic chalcone derivatives on HCT116 cells. (E)-2-(2',4'-dimethoxybenzylidene)-1-tetralone (Q705) was found to be the most active (IC50 = 3.44 ± 0.25 µM). Based on these results, this compound was chosen for further analysis of its biochemical and molecular mechanisms. Our results showed that Q705 inhibited the growth and clonogenicity of HCT116 cells. The results of a flow cytometric analyses suggested that this compound caused a significant cell cycle arrest in G2/M phase and increased the proportion of cells in the subG0/G1 phase, marker of apoptosis. Q705-induced apoptosis was confirmed by TdT-mediated dUTP nick end labelling (TUNEL) assay. Treatment of HCT116 cells with this chalcone significantly increased the caspase-3,-7 activity and resulted in cleavage of poly-ADP-ribose polymerase (PARP). Changes in the nuclear morphology such as chromatin condensation were also observed. These effects were associated with a decreased expression of bcl-xL and increased overall ratio of bax/bcl-xL mRNA levels. Immunofluorescence and qRT-PCR analysis revealed that Q705 induced H2AX histone modifications characteristic of DNA damage, disruption of microtubule organization and downregulation of tubulins. In summary, these results suggest that the cyclic chalcone analogue Q705 has potential as a new compound for colorectal cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Compostos de Benzilideno/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Chalconas/farmacologia , Neoplasias Colorretais/patologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Imunofluorescência , Células HCT116 , Humanos , Marcação In Situ das Extremidades Cortadas , Reação em Cadeia da Polimerase em Tempo Real
14.
PLoS Comput Biol ; 9(10): e1003293, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24146610

RESUMO

The antiproliferative response to anticancer treatment is the result of concurrent responses in all cell cycle phases, extending over several cell generations, whose complexity is not captured by current methods. In the proposed experimental/computational approach, the contemporary use of time-lapse live cell microscopy and flow cytometric data supported the computer rendering of the proliferative process through the cell cycle and subsequent generations during/after treatment. The effects of treatments were modelled with modules describing the functional activity of the main pathways causing arrest, repair and cell death in each phase. A framework modelling environment was created, enabling us to apply different types of modules in each phase and test models at the complexity level justified by the available data. We challenged the method with time-course measures taken in parallel with flow cytometry and time-lapse live cell microscopy in X-ray-treated human ovarian cancer cells, spanning a wide range of doses. The most suitable model of the treatment, including the dose-response of each effect, was progressively built, combining modules with a rational strategy and fitting simultaneously all data of different doses and platforms. The final model gave for the first time the complete rendering in silico of the cycling process following X-ray exposure, providing separate and quantitative measures of the dose-dependence of G1, S and G2M checkpoint activities in subsequent generations, reconciling known effects of ionizing radiations and new insights in a unique scenario.


Assuntos
Ciclo Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Modelos Biológicos , Neoplasias Ovarianas/radioterapia , Linhagem Celular Tumoral , Simulação por Computador , Relação Dose-Resposta à Radiação , Feminino , Humanos , Microscopia de Vídeo , Imagem com Lapso de Tempo
15.
Nanotechnology ; 25(4): 045102, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24398665

RESUMO

Studies of cellular internalization of nanoparticles (NPs) play a paramount role for the design of efficient drug delivery systems, but so far they lack a robust experimental technique able to quantify the NP uptake in terms of number of NPs internalized in each cell. In this work we propose a novel method which provides a quantitative evaluation of fluorescent NP uptake by combining flow cytometry and plate fluorimetry with measurements of number of cells. Single cell fluorescence signals measured by flow cytometry were associated with the number of internalized NPs, exploiting the observed linearity between average flow cytometric fluorescence and overall plate fluorimeter measures, and previous calibration of the microplate reader with serial dilutions of NPs. This precise calibration has been made possible by using biocompatible fluorescent NPs in the range of 20-300 nm with a narrow particle size distribution, functionalized with a covalently bonded dye, Rhodamine B, and synthesized via emulsion free-radical polymerization. We report the absolute number of NPs internalized in mouse mammary tumor cells (4T1) as a function of time for different NP dimensions and surface charges and at several exposure concentrations. The obtained results indicate that 4T1 cells incorporated 10(3)-10(4) polymer NPs in a short time, reaching an intracellular concentration 15 times higher than the external one.


Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Espectrometria de Fluorescência , Animais , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Portadores de Fármacos/química , Feminino , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Radicais Livres , Cinética , Neoplasias Mamárias Animais/patologia , Camundongos , Microscopia Confocal , Tamanho da Partícula , Polímeros/química , Rodaminas/química
17.
J Biol Chem ; 287(31): 25782-94, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22669976

RESUMO

Spinal muscular atrophy is a fatal genetic disease of motoneurons due to loss of full-length survival of motor neuron protein, the main product of the disease gene SMN1. Axonal SMN (a-SMN) is an alternatively spliced isoform of SMN1, generated by retention of intron 3. To study a-SMN function, we generated cellular clones for the expression of the protein in mouse motoneuron-like NSC34 cells. The model was instrumental in providing evidence that a-SMN decreases cell growth and plays an important role in the processes of axon growth and cellular motility. In our conditions, low levels of a-SMN expression were sufficient to trigger the observed biological effects, which were not modified by further increasing the amounts of the expressed protein. Differential transcriptome analysis led to the identification of novel a-SMN-regulated factors, i.e. the transcripts coding for the two chemokines, C-C motif ligands 2 and 7 (CCL2 and CCL7), as well as the neuronal and myotrophic factor, insulin-like growth factor-1 (IGF1). a-SMN-dependent induction of CCL2 and IGF1 mRNAs resulted in increased intracellular levels and secretion of the respective protein products. Induction of CCL2 contributes to the a-SMN effects, mediating part of the action on axon growth and random cell motility, as indicated by chemokine knockdown and re-addition studies. Our results shed new light on a-SMN function and the underlying molecular mechanisms. The data provide a rational framework to understand the role of a-SMN deficiency in the etiopathogenesis of spinal muscular atrophy.


Assuntos
Axônios/fisiologia , Movimento Celular , Quimiocina CCL2/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Neurônios/fisiologia , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo , Axônios/metabolismo , Linhagem Celular , Proliferação de Células , Forma Celular , Quimiocina CCL2/genética , Quimiocina CCL7/genética , Quimiocina CCL7/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Fator de Crescimento Insulin-Like I/genética , Neurônios/metabolismo , Transporte Proteico , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 1 de Sobrevivência do Neurônio Motor/fisiologia , Transcrição Gênica , Transcriptoma
18.
Nanotechnology ; 24(24): 245603, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23690139

RESUMO

Efficient application of stem cells to the treatment of neurodegenerative diseases requires safe cell tracking to follow stem cell fate over time in the host environment after transplantation. In this work, for the first time, fluorescent and biocompatible methyl methacrylate (MMA)-based nanoparticles (fluoNPs) were synthesized through a free-radical co-polymerization process with a fluorescent macromonomer obtained by linking Rhodamine B and hydroxyethyl methacrylate. We demonstrate that the fluoNPs produced by polymerization of MMA-Rhodamine complexes (1) were efficient for the labeling and tracking of multipotent human amniotic fluid cells (hAFCs); (2) did not alter the main biological features of hAFCs (such as viability, cell growth and metabolic activity); (3) enabled us to determine the longitudinal bio-distribution of hAFCs in different brain areas after graft in the brain ventricles of healthy mice by a direct fluorescence-based technique. The reliability of our approach was furthermore confirmed by magnetic resonance imaging analyses, carried out by incubating hAFCs with both superparamagnetic iron oxide nanoparticles and fluoNPs. Our data suggest that these finely tunable and biocompatible fluoNPs can be exploited for the longitudinal tracking of stem cells.


Assuntos
Materiais Biocompatíveis/farmacologia , Rastreamento de Células/métodos , Nanopartículas/química , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Endocitose/efeitos dos fármacos , Citometria de Fluxo , Fluorescência , Corantes Fluorescentes/química , Humanos , Implantes Experimentais , Imageamento por Ressonância Magnética , Camundongos , Microscopia Confocal , Nanopartículas/ultraestrutura , Coloração e Rotulagem , Transplante de Células-Tronco , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Imagem com Lapso de Tempo
19.
J Biol Chem ; 286(5): 4027-42, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21131358

RESUMO

Retinoids are promising agents for the treatment/prevention of breast carcinoma. We examined the role of microRNAs in mediating the effects of all-trans-retinoic acid (ATRA), which suppresses the proliferation of estrogen receptor-positive (ERα(+)) breast carcinoma cells, such as MCF-7, but not estrogen receptor-negative cells, such as MDA-MB-231. We found that pro-oncogenic miR-21 is selectively induced by ATRA in ERα(+) cells. Induction of miR-21 counteracts the anti-proliferative action of ATRA but has the potentially beneficial effect of reducing cell motility. In ERα(+) cells, retinoid-dependent induction of miR-21 is due to increased transcription of the MIR21 gene via ligand-dependent activation of the nuclear retinoid receptor, RARα. RARα is part of the transcription complex present in the 5'-flanking region of the MIR21 gene. The receptor binds to two functional retinoic acid-responsive elements mapping upstream of the transcription initiation site. Silencing of miR-21 enhances ATRA-dependent growth inhibition and senescence while reverting suppression of cell motility afforded by the retinoid. Up-regulation of miR-21 results in retinoid-dependent inhibition of the established target, maspin. Knockdown and overexpression of maspin in MCF-7 cells indicates that the protein is involved in ATRA-induced growth inhibition and contributes to the ATRA-dependent anti-motility responses. Integration between whole genome analysis of genes differentially regulated by ATRA in MCF-7 and MDA-MB-231 cells, prediction of miR-21 regulated genes, and functional studies led to the identification of three novel direct miR-21 targets: the pro-inflammatory cytokine IL1B, the adhesion molecule ICAM-1 and PLAT, the tissue-type plasminogen activator. Evidence for ICAM-1 involvement in retinoid-dependent inhibition of MCF-7 cell motility is provided.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , MicroRNAs/genética , Tretinoína/farmacologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Feminino , Estudo de Associação Genômica Ampla , Humanos , Molécula 1 de Adesão Intercelular/genética , Interleucina-1/genética , Receptores de Estrogênio , Ativador de Plasminogênio Tecidual/genética , Ativação Transcricional/efeitos dos fármacos
20.
Cancers (Basel) ; 14(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35406579

RESUMO

BACKGROUND: Poly(ADP-ribose) polymerases inhibitor (PARPi) have shown clinical efficacy in ovarian carcinoma, especially in those harboring defects in homologous recombination (HR) repair, including BRCA1 and BRCA2 mutated tumors. There is increasing evidence however that PARPi resistance is common and develops through multiple mechanisms. METHODS: ID8 F3 (HR proficient) and ID8 Brca1-/- (HR deficient) murine ovarian cells resistant to olaparib, a PARPi, were generated through stepwise drug concentrations in vitro. Both sensitive and resistant cells lines were pharmacologically characterized and the molecular mechanisms underlying olaparib resistance. RESULTS: In ID8, cells with a HR proficient background, olaparib resistance was mainly caused by overexpression of multidrug resistance 1 gene (MDR1), while multiple heterogeneous co-existing mechanisms were found in ID8 Brca1-/- HR-deficient cells resistant to olaparib, including overexpression of MDR1, a decrease in PARP1 protein level and partial reactivation of HR repair. Importantly, combinations of ATR, Chk1 and Wee1 inhibitors with olaparib were synergistic in sensitive and resistant sublines, regardless of the HR cell status. CONCLUSION: Olaparib-resistant cell lines were generated and displayed multiple mechanisms of resistance, which will be instrumental in selecting new possible therapeutic options for PARPi-resistant ovarian tumors.

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